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191.
Juvenile xanthogranuloma is an infrequent, benign, normolipemic, non-Langerhans cell histiocytosis, which primarily affects young children. Clinically, it is characterized by the appearance of one or several brownish-yellow papulonodular lesions on the upper body, especially on the head and neck. Xanthogranulomas are less frequent in adults, and generally present as solitary lesions. The diagnosis of multiple xanthogranulomas in adults is exceptional. We describe the case of a female patient diagnosed with this rare disease.  相似文献   
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In the present report we have assessed the extent to which Ficoll-Paque separation and cryopreservation of mononuclear cells alter the measurement of lymphocyte subsets by flow cytometry. Standard Ficoll-Paque separation increased the percentage of CD4+, CD19+ and CD4+CD45RA+ cells, as well as decreasing that of CD8+, and CD4+CD29+ cells, compared to the fresh whole blood lysis technique. Moreover, cryopreservation caused a depletion of CD4+ p80+ cells, but normal whole blood values were restored following a short incubation.  相似文献   
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Recurrent Bell's palsy is a rare form of facial paralysis. To investigate the role which cellular immunity plays in the aetiology of recurrent Bell's palsy, we evaluated a series of such patients using a laboratory test specially formulated to test the cellular immune system. We measured T-lymphocyte and T-lymphocyte subsets in the peripheral blood of 10 recurrent Bell's palsy patients and in 30 healthy volunteers. T-lymphocytes and T-lymphocyte subsets were reduced significantly in the patients, but the T-helper: T-cytotoxic ratio was normal. Cellular immunity abnormalities were therefore found in the peripheral blood of patients with recurrent Bell's palsy, supporting the concept that this is an immunomediated demyelinating disease.  相似文献   
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Transgenic mice expressing the c-Myc oncogene driven by woodchuck hepatitis virus (WHV) regulatory sequences develop hepatocellular carcinoma with a high frequency. To investigate genetic lesions that cooperate with Myc in liver carcinogenesis, we conducted a genome-wide scan for loss of heterozygosity (LOH) and mutational analysis of beta-catenin in 37 hepatocellular adenomas and carcinomas from C57BL/6 x castaneus F1 transgenic mice. In a subset of these tumors, chromosome imbalances were examined by comparative genomic hybridization (CGH). Allelotyping with 99 microsatellite markers spanning all autosomes revealed allelic imbalances at one or more chromosomes in 83.8% of cases. The overall fractional allelic loss was rather low, with a mean index of 0.066. However, significant LOH rates involved chromosomes 4 (21.6% of tumors), 14, 9 and 1 (11 to 16%). Interstitial LOH on chromosome 4 was mapped at band C4-C7 that contains the INK4a/ARF and INK4b loci, and on chromosome 14 at band B-D including the RB locus. In man, the homologous chromosomal regions 9p21, 13q14 and 8p21-23 are frequently deleted in liver cancer. LOH at chromosomes 1 and 14, and beta-catenin mutations (12.5% of cases) were seen only in HCCs. All tumors examined were found to be aneuploid. CGH analysis of 10 representative cases revealed recurrent gains at chromosomes 16 and 19, but losses or deletions involving mostly chromosomes 4 and 14 generally prevailed over gains. Thus, Myc activation in the liver might select for inactivation of tumor suppressor genes on regions of chromosomes 4 and 14 in a context of low genomic instability. Myc transgenic mice provide a useful model for better defining crosstalks between oncogene and tumor suppressor pathways in liver tumorigenesis.  相似文献   
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Hypertrophic cardiomyopathy (HCM) is a heterogeneous disease, characterized by asymmetric hypertrophy of the left and/or right ventricle with disarray of myocardial fibers. In order to know its clinical and electrocardiographic manifestation in the pediatric age group, we made a retrospective study of 24 cases from 1986 to 1995. There were: 15 girls and 9 boys, with a mean age of 6 years (age range: 1 month to 17 years). Clinical manifestations were dyspnea (71%), syncope (42%) and palpitations (42%). Physical examination disclosed an aortic systolic murmur in all patients, a mitral regurgitation in 42% and physical signs of congestive heart failure in 54% of patients. Chest X rays showed cardiac enlargement in 71% and pulmonary capillary hypertension in 42%. The most frequent ECG abnormalities were: a prolonged time in the intrinsecoid deflection onset on leads corresponding to the affected region, more or less deep and clean Q waves on leads aVF, aVL, V5 and V6, as well as supraventricular and ventricular rhythm disturbances in 11 patients (46%) with and without congestive heart failure. Bidimensional echocardiography confirmed antero-septal hypertrophy in all patients. The mortality rate was 17%. HCM is rare disease in the pediatric age group. Mortality increases when congestive heart failure and arrhythmias are present. Treatment must be individualized in all cases.  相似文献   
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Since 1965, 46 patients aged 4 to 42 years, underwent cardiac surgery for subaortic stenosis. Resection of the subvalvar obstruction without myomectomy was performed in all cases. Three patients died during the operation, another one after 6 months due to infective endocarditis and one more suddenly 11 years after treatment. One patient was lost to follow-up but 41 were available after at least 1 year of follow-up. Before surgery, 21 cases were in NYHA class I, 17 in class II and 8 in class III. One year after surgery 36 were in class I, 4 in class II and only one in class III. Actuarial survival rate was 91% from 1 to 12 years and 79% from 13 to 18 years. Event-free survival was 45% up to 18 years. The mean preoperative peak systolic gradient was 93.15 +/- 35.57 mm Hg. The first postoperative peak systolic gradient was 21.61 +/- 17.91 mm Hg (P = 0.001). Cases with adverse postoperative events such as aortic regurgitation (13 cases), restenosis (13 cases), death (2 cases) and infective endocarditis (2 cases) had a mean peak systolic gradient of 55.78 +/- 35.97 mm Hg, while in the event-free patients the gradient was 14.61 +/- 13.34 mm Hg (P = 0.001). Recurrent obstruction was observed in seven patients and an increase in the residual gradient in six. The initial mean postoperative peak systolic gradient in these patients had been 18.23 +/- 17.32 mm Hg and the second postoperative cardiac catheterisation showed a mean gradient of 59.23 +/- 37.78 mm Hg (P = 0.001). We conclude that long-term follow-up following removal of subaortic stenosis is mandatory in order to detect and treat adverse events.  相似文献   
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AIMS: The purpose of this work is to study the validity of the Severity of Dependence Scale (SDS) construct by applying Rasch models to a non-clinical sample of heroin abusers. SUBJECTS: 982 (73% men) young people 30 years old or under (mean age 25.9 years) participated. All of them were captured from the community in the metropolitan areas of Madrid, Barcelona and Seville, between April 2002 and December 2003. ANALYSIS: Dimensionality of the scale and calibration of items were studied using the Rating Scale model, which is a Rasch-type model. A factorial analysis was also performed to check the dimensionality of the scale. RESULTS: The analysis of fit shows that all the items have infit and outfit values between +/- 2 logits, indicating that the data fit the model and that it may be assumed to be unidimensional. The principal components analysis also showed the existence of a principal factor that explains 52.5% of the variance observed. Item calibration found that they are between +0.89 and -1.04 logits on the scale. CONCLUSION: The results show unidimensional structure of the SDS scale. Item calibration shows they are distributed along the continuum, which must be taken into account when calculating total scores. The study's limitations are noted.  相似文献   
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